1266540879 has 4 divisors (see below), whose sum is σ = 1688721176. Its totient is φ = 844360584.

The previous prime is 1266540827. The next prime is 1266540889. The reversal of 1266540879 is 9780456621.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 1266540879 - 2⁸ = 1266540623 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1266540889) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 211090144 + ... + 211090149.

It is an arithmetic number, because the mean of its divisors is an integer number (422180294).

Almost surely, 2^1266540879 is an apocalyptic number.

1266540879 is a deficient number, since it is larger than the sum of its proper divisors (422180297).

1266540879 is an equidigital number, since it uses as much as digits as its factorization.

1266540879 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 422180296.

The product of its (nonzero) digits is 725760, while the sum is 48.

The square root of 1266540879 is about 35588.4936320716. The cubic root of 1266540879 is about 1081.9480384890.

The spelling of 1266540879 in words is "one billion, two hundred sixty-six million, five hundred forty thousand, eight hundred seventy-nine".